The term is used to describe symptoms experienced by individuals working or living in large commercial buildings when no other cause for their illness can be detected. Dr. Bill Wolverton, a leading scientist in NASA's Clean Air Study, explains, "When the building occupants are away for a given time, the symptoms usually diminish, only to recur upon re-entry into the building."

These symptoms can include sudden allergies, headache, dizziness, fatigue, respiratory and sinus congestion, and nervous system disorders.

So what's the cause of the majority of these symptoms? Indoor air pollution.

The Environmental Protection Agency now ranks indoor air pollution among the top five threats to human health. Not great news when studies indicate that people spend approximately 90 percent of their time indoors. Indoor air pollution can be caused by a variety of factors, but the most common contributors are mold, pollen, various smoke and gases, household cleaning products, pesticides, synthetic building materials, and poor air circulation. These contributors release toxins such as benzene, formaldehyde, trichloroethylene, xylene, and toluene.

It is important to try to improve your indoor air quality in the home and office even if symptoms are not noticeable now. And one of the best ways to do that is with indoor plants.

Indoor plants don't just look good—they make us feel good mentally and physically, too. They absorb atmospheric toxins and break them down into gentile organic by-products. Studies show that indoor plants can boost morale, productivity, concentration and creativity, and reduce stress, fatigue, sore throats, and colds.

Plants have proved especially beneficial in office settings. They've been shown to improve staff well-being and reduce sick-leave absences. Contact with bits of nature has also been proven to reduce mental fatigue and stress and increase relaxation and self-esteem. Even brief exposure to nature has been shown to make us more altruistic and cooperative. In a 2013 study, touching real foliage—rather than fake foliage made from resin—was shown to elicit an unconscious calming effect on participants.

That's why The Sill just partnered with the Breather app to open "The Oasis," an on-demand botanical sanctuary, in Manhattan for the spring season. We hope that "The Oasis" will offer an escape for New Yorkers, away from the concrete, horns, and winter blues, and serve as an ideal workspace for entrepreneurs, professionals, freelancers, and beyond.

In addition to looking great aesthetically, the indoor plants at "The Oasis" are intended to promote physical and mental wellness, as they have been proven to boost morale, productivity, concentration, and creativity.

Here are a few of the toxin-busting varieties we chose for the space. Take a look, and think about adding a few to your home or office this spring.